Is it possible to write a script which opens Blender's existing FBX exporter window?
Use bpy.ops.export_scene.fbx('INVOKE_DEFAULT').
More info about &quot;Execution Contexts&quot;: https://docs.blender.org/api/2.79/bpy.ops.html?highlight=invoke#execution-context
I'm not sure what the best way to run something after the operator is complete is though. Maybe try: Running code after a modal operator finished its job